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排序方式: 共有320条查询结果,搜索用时 781 毫秒
191.
Mahendra Shukla Swati Jaiswal Abhisheak Sharma Pradeep Kumar Srivastava Abhishek Arya Anil Kumar Dwivedi 《Drug development and industrial pharmacy》2017,43(5):847-861
AbstractObjective: Curcumin, the golden spice from Indian saffron, has shown chemoprotective action against many types of cancer including breast cancer. However, poor oral bioavailability is the major hurdle in its clinical application. In the recent years, self-nanoemulsifying drug delivery system (SNEDDS) has emerged as a promising tool to improve the oral absorption and enhancing the bioavailability of poorly water-soluble drugs. In this context, complexation with lipid carriers like phospholipid has also shown the tremendous potential to improve the solubility and therapeutic efficacy of certain drugs with poor oral bioavailability.Methods: In the present investigation, a systematic combination of both the approaches is utilized to prepare the phospholipid complex of curcumin and facilitate its incorporation into SNEDDS. The combined use of both the approaches has been explored for the first time to enhance the oral bioavailability and in turn increase the anticancer activity of curcumin.Results: As evident from the pharmacokinetic studies and in situ single pass intestinal perfusion studies in Sprague–Dawley rats, the optimized SNEDDS of curcumin–phospholipid complex has shown enhanced oral absorption and bioavailability of curcumin. The cytotoxicity study in metastatic breast carcinoma cell line has shown the enhancement of cytotoxic action by 38.7%. The primary tumor growth reduction by 58.9% as compared with the control group in 4T1 tumor-bearing BALB/c mice further supported the theory of enhancement of anticancer activity of curcumin in SNEDDS.Conclusion: The developed formulation can be a potential and safe carrier for the oral delivery of curcumin. 相似文献
192.
Pathak Yadunath Arya K. V. Tiwari Shailendra 《Multimedia Tools and Applications》2019,78(11):14733-14752
Multimedia Tools and Applications - Low-dose Computed Tomography (CT) reconstruction techniques have been implemented to minimize the X-ray radiation in a human body. Many researchers have designed... 相似文献
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Plasmonic hot spots are formed when metal surfaces with high curvature are separated by nanoscale gaps and an electromagnetic field is localized within the gaps. These hot spots are responsible for phenomena such as subwavelength focusing, surface-enhanced Raman spectroscopy and electromagnetic transparency, and depend on the geometry of the nanojunctions between the metal surfaces. Direct-write techniques such as electron-beam lithography can create complex nanostructures with impressive spatial control but struggle to fabricate gaps on the order of a few nanometres or manufacture arrays of nanojunctions in a scalable manner. Self-assembly methods, in contrast, can be carried out on a massively parallel scale using metal nanoparticle building blocks of specific shape. Here, we show that polymer-grafted metal nanocubes can be self-assembled into arrays of one-dimensional strings that have well-defined interparticle orientations and tunable electromagnetic properties. The nanocubes are assembled within a polymer thin film and we observe unique superstructures derived from edge-edge or face-face interactions between the nanocubes. The assembly process is strongly dependent on parameters such as polymer chain length, rigidity or grafting density, and can be predicted by free energy calculations. 相似文献
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Neha Arya Viren Sardana Meera Saxena Annapoorni Rangarajan Dhirendra S. Katti 《Journal of the Royal Society Interface》2012,9(77):3288-3302
Owing to the reduced co-relationship between conventional flat Petri dish culture (two-dimensional) and the tumour microenvironment, there has been a shift towards three-dimensional culture systems that show an improved analogy to the same. In this work, an extracellular matrix (ECM)-mimicking three-dimensional scaffold based on chitosan and gelatin was fabricated and explored for its potential as a tumour model for lung cancer. It was demonstrated that the chitosan–gelatin (CG) scaffolds supported the formation of tumoroids that were similar to tumours grown in vivo for factors involved in tumour-cell–ECM interaction, invasion and metastasis, and response to anti-cancer drugs. On the other hand, the two-dimensional Petri dish surfaces did not demonstrate gene-expression profiles similar to tumours grown in vivo. Further, the three-dimensional CG scaffolds supported the formation of tumoroids, using other types of cancer cells such as breast, cervix and bone, indicating a possible wider potential for in vitro tumoroid generation. Overall, the results demonstrated that CG scaffolds can be an improved in vitro tool to study cancer progression and drug screening for solid tumours. 相似文献
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Tarlochan Singh Rajendra Kumar Arya Akshay Dvivedi 《Machining Science and Technology》2020,24(2):195-226
AbstractIn the present work, rotary mode electrochemical discharge drilling (RM-ECDD) was employed to machine the Al-6063 SiCp metal matrix composites (MMC’s). The effect of various process parameters such as applied voltage, pulse on time, tool rotation rate, electrolyte concentration and current on quality characteristics (hole over cut and depth of penetration) of the drilled holes was investigated. The underlying material removal mechanism during the machining of MMC’s with RM-ECDD is also proposed by considering the scanning electron micrographs (SEM) and simulation results as an evidences. A comparative analysis between RM-ECDD and ECDD was performed during the machining of MMC’s. The experimental results reveal that the integration of tool rotations in ECDD successfully evacuates the sludge/debris from the machining zone, and it also replenishes the electrolyte effectively. Therefore the use of RM-ECDD improves the aspect ratio (L/D), and it exhibits 23.07 times higher L/D ratio than the ECDD process. In ECDM, the discharge characteristics are very important outcome that explores the significant details of the involved mechanisms and phenomena of the process. In the present research, a DSO recorded voltage signals were used to understand the discharge behavior and their characteristics at different parameter combinations. This paper also presents a second-order mathematical models to determine the relation between input process parameters and quality characteristics. Desirability based multi objective optimization approach was employed to optimize the process parameters. 相似文献
199.
LCA of second generation bioethanol: A review and some issues to be resolved for good LCA practice 总被引:1,自引:0,他引:1
Edi Iswanto Wiloso Reinout Heijungs Geert R. de Snoo 《Renewable & Sustainable Energy Reviews》2012,16(7):5295-5308
This paper aims at reviewing the life cycle assessment (LCA) literature on second generation bioethanol based on lignocellulosic biomass and at identifying issues to be resolved for good LCA practice. Reviews are carried out on respective LCA studies published over the last six years. We use the classification of lignocellulosic biomass to define system boundaries, so that the comparison among LCA results can be thoroughly assessed based on identified system components. A basis for attributing environmental burden for different biomass feedstocks is also suggested. Despite the non-homogeneous systems, we conclude that second generation bioethanol performs better than fossil fuel at least for the two most studied impact categories, net energy output and global warming. For the latter category, carbon sequestration at the biomass generation stage can even consistently offset the GHG emissions from all parts of the life cycle chains at high ethanol percentage (≥85%). The aspect of biogenic carbon and agrochemical input for energy crops and biomass residues, and the effect of removal of the latter from soil have not been treated consistently. In contrast, the exclusion of upstream chain of biomass waste feedstocks is observed in practice. The bioethanol conversion process is mostly based on simultaneous saccharification and co-fermentation, characterized by high yield and low energy input. In this regard, the LCA results tend to under estimate the real impacts of the current technology. The choice of allocation methods strongly influences the final results, particularly when economic value is used as a reference. Substitution of avoided burden seems to be the most popular allocation method in practice, followed by partition based on mass, energy, and economic values. 相似文献
200.